Since beginning his tenure as the world's top diplomat nearly three years ago, Ban Ki-moon has pressed the international community to take serious action to halt the effects of global warming. Now, with his prestige on the line, he heads to the Danish capital where difficult and complex climate talks are at risk of failing.
"Time is running out,” he told reporters. “There is no time left for posturing or blaming. Every country must do its part to seal a deal in Copenhagen."
The United Nations has already backed away from its original hope of getting a legally binding treaty this week and says success will be a serious agreement that will lead the way to a legally binding one next year.
Mr. Ban told reporters the choice is clear. "We can move toward a future of sustainable green growth, or we can continue down the road to ruin. We can act on climate change now, or we can leave it to our children and grandchildren - a debt that can never be paid. It will threaten the future of our planet and its people," said the secretary-general.
He appealed to the negotiators who are laying the groundwork for the summit, asking them to redouble their efforts in this final stretch before the 115 world leaders arrive later this week.
"If everything is left to the leaders to resolve at the last minute, we risk having a weak deal - or no deal at all,” he said. “And this would be a failure of potentially catastrophic consequence."
Mr. Ban said he believes there has been tangible progress on key issues, including technology cooperation and financing. That includes an agreement by wealthy countries to provide $10 billion each year through 2012 to help developing countries adapt to and offset the impacts of climate change. But he said greater clarity is needed on a robust financing package for the middle and longer term.
Other key issues remain unresolved, including commitments from developed countries on how much they will cut their greenhouse gas emissions during the next 40 years, and whether nations can keep the planet's temperature from rising no more than 1.5 or two degrees Celsius.